Battery warranty is 8 YEARS and 100K miles from the initial service date when car was actually sold. Therefore if you get down to 13.2kW in the secret BC menu you should demand battery replacement.
Google " bmw i3 BC battery check "
You must check the actual amount of battery/energy storage capability for warranty: 18.8 is the starting point, when its in the 13 range before 8 years or 100,000 miles you can demand a free battery. Mileage is NOT warranty related. Hope that helps.
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